Multiply recurrent retroperitoneal liposarcoma

Surgical management of giant retroperitoneal liposarcoma: Case report

Tumors originating from soft tissues are uncommon, among these tumors, liposarcomas are the most frequent. These tumors remain asymptomatic for a long time, and only revealing themselves when they reach an important size. In such cases, treatment is difficult, requiring extensive surgery procedures that can excise several adjacent structures, potentially completed by adjuvant radiotherapy. Despite successful treatment, the recurrence rate remains very high. We report the case of a giant liposarcoma requiring a monobloc extensive resection involving the removal of the tumor, left kidney, left adrenal gland, and a portion of the posterior abdominal wall.

Pleomorphic Liposarcoma Unraveled: Investigating Histopathological and Immunohistochemical Markers for Tailored Diagnosis and Therapeutic Innovations

Liposarcomas are some of the most challenging soft tissue tumors and are subclassified into multiple subtypes with special histologic and molecular features. The peculiarities of each histopathological subtype influence the clinical behavior, management, and treatment of these neoplasms. For instance, well-differentiated liposarcomas are common soft tissue malignancies and usually display a favorable outcome. On the other hand, pleomorphic liposarcoma is the rarest, yet the most aggressive subtype of liposarcoma. This histopathological diagnosis may be challenging due to the scarce available data and because pleomorphic liposarcomas can mimic other pleomorphic sarcomas or other neoplasms of dissimilar differentiation. Nevertheless, the correct diagnosis of pleomorphic liposarcoma is of utmost importance as such patients are prone to develop local recurrences and metastases. Treatment usually consists of surgical excision along with radiotherapy and follow-up of the patients. Therefore, this review aims to assess the complex clinical, histological, and immunohistochemical features of liposarcomas in order to establish how these characteristics influence the management and prognosis of the patients, emphasizing the particularities of pleomorphic liposarcoma.

The significance of a 'T shaped' incision for resection of giant mediastinal tumors: a case report

A 37-year-old male, with a 5-year history of liposarcoma of the right thigh, was incidentally diagnosed with two huge thoracic metastases following a fall. One of these masses, measuring 22 cm, was located in the right chest apex, adjacent to a second 20 cm mass situated in the anterior mediastinum, partially invading the left chest. The patient underwent surgical intervention for mass resection that commenced with a hemi-clamshell incision, but was then extended by completing the lower median sternotomy in order to create a T shaped incision. This type of incision provides ample access for large mediastinal tumors that extensively extend into one side of the thoracic cavity, encompass the anterior mediastinum, and partially reach into the opposite cavity. It enhances visualization, facilitates access to vital organs, allows for precise surgical maneuvers, minimizes the risk of inadvertent tissue damage, and enables thorough oncological resection.

Recurrence of locally invasive retroperitoneal dedifferentiated liposarcoma shortly after surgery: A case report and literature review

RATIONALE

Retroperitoneal dedifferentiated liposarcoma (RPDDL) is an uncommon malignancy, which often remains undetected for many years due to having adequate space in the retroperitoneal cavity and lacking clinical manifestations in the early stage of the disease. Surgical procedure is usually used as the first choice for treatment. However, it is prone to local recurrence after the operation, resulting in an unfavorable prognosis. Our aim is to draw useful lessons from the new case and provide some experience for management of the disease.

PATIENT CONCERNS

We describe a 55-year-old male patient who was admitted for a 3-week history of persistent dull ache of the left waist. A large mass of the left upper abdomen was palpated in physical examination. Moreover, the imaging examination revealed that the diameter of the mass was about 21 cm, and some adjacent vital organs were invaded, which brought great challenges to complete surgical resection.

DIAGNOSIS

The postoperative pathological results confirmed that the mass was RPDDL with invasion of the surrounding vital structures including pancreas, spleen, left adrenal gland, left kidney, and vasculature with tumor emboli.

INTERVENTIONS

Surgical resection of the mass was performed by our multidisciplinary team. The patient received chemotherapy 1 month after surgery.

OUTCOMES

The effect of chemotherapy seemed to be unsatisfactory. Local multifocal recurrence of the tumor was considered about 2 months after surgery. Finally, he gave up any treatments and died of the disease.

LESSONS

Regular physical examination and ultrasound screening may detect the disease as early as possible, especially for high-risk group aged 60 to 70, which should be popularized. Incomplete resection, vascular invasion, and interruption of postoperative treatment may lead to an unfavorable prognosis. Therefore, we think that patients with the disease may benefit from complete surgical resection and uninterrupted adjuvant therapy.

Identification of predictors for short-term recurrence: comprehensive analysis of 296 retroperitoneal liposarcoma cases

BACKGROUND

The short-term (≤ 1 year) recurrence (STR) is the primary determinant impacting both the life quality and survival duration in patients who have undergone surgical resection for retroperitoneal liposarcoma (RPLS), a condition with intricate and ambiguous pathogenesis. The purpose of this study was to analyze the risk factors associated with STR in cases of RPLS and primary retroperitoneal liposarcoma (PRPLS).

METHODS

For this retrospective observational study, a total of 296 RPLS cases were selected as research subjects, who experienced tumor recurrence during the follow-up period. The Local recurrence-free survival (LRFS) rates were estimated using the Kaplan-Meier method and subsequently compared between groups utilizing the log-rank test. The subsequent analyses involved univariate and multivariate logistic regression to identify predictors of STR in RPLS cases. Additionally, a logistic regression model was constructed for PRPLS.

RESULTS

The 1-, 3-, and 5-year LRFS rates of the 296 RPLS cases were 51.7%, 16.9%, and 7.1%, respectively. In the univariate analysis, several factors were found to be associated with STR, including preoperative neutrophil/lymphocyte ratio (NLR), smoking history, surgical frequency, combined organ excision, operative time, intraoperative bleeding, transfer to the intensive care unit (ICU), multiple primary tumors, tumor shape and capsule characteristics, histological subtype, and presence of tumor necrosis. The elevated preoperative NLR, surgical frequency of ≥ 3 times, transfer to the ICU, presence of multiple primary tumors, and tumor necrosis were identified as independent risk factors for STR in surgically resected RPLS. Conversely, diabetes, intact tumor capsule, and well-differentiated histological subtype appeared to be independent protective factors. Analysis for PRPLS revealed that tumor capsule and tumor necrosis were independent predictors of STR.

CONCLUSIONS

The elevated preoperative NLR, surgical frequency of ≥ 3 times, transfer to the ICU, presence of multiple primary tumors, tumor necrosis, and tumor capsule were expected to serve as predictive factors of STR for surgical resected RPLS and PRPLS.

Predictors and outcomes of recurrent retroperitoneal liposarcoma: new insights into its recurrence patterns

BACKGROUND

The clinical profiles of recurrent retroperitoneal liposarcoma (RLS) need to be explored. The recurrence patterns of RLS are controversial and ambiguous.

METHODS

A total of 138 patients with recurrent RLS were finally recruited in the study. The analysis of overall survival (OS) and recurrence-free survival (RFS) was performed by Kaplan‒Meier analysis. To identify independent prognostic factors, all significant variables on univariate Cox regression analysis (P ≤ 0.05) were subjected to multivariate Cox regression analysis. The corresponding nomogram model was further built to predict the survival status of patients.

RESULTS

Among patients, the 1-, 3-, and 5-year OS rates were 70.7%, 35.9% and 30.9%, respectively. The 1-, 3- and 5-year RFS rates of the 55 patients who underwent R0 resection were 76.1%, 50.8% and 34.4%, respectively. The multivariate analysis revealed that resection method, tumor size, status of pathological differentiation, pathological subtypes and recurrence pattern were independent risk factors for OS or RFS. Patients with distant recurrence (DR) pattern usually had multifocal tumors (90.5% vs. 74.7%, P < 0.05); they were prone to experience changes of pathological differentiation (69.9% vs. 33.3%, P < 0.05) and had a better prognosis than those with local recurrence (LR) pattern. R0 resection and combined organ resection favored the survival of patients with DR pattern in some cases.

CONCLUSIONS

Patients with DR pattern had better prognosis, and they may benefit more from aggressive combined resection than those with LR pattern. Classifying the recurrence patterns of RLS provides guidance for individualized clinical management of recurrent RLS.

Predictors and outcomes of recurrent retroperitoneal liposarcoma with multiple tumors

Background

Retroperitoneal liposarcoma (RLS) is a rare but severe disease. Repeated postoperative recurrence with multiple tumors is a therapeutic dilemma. The clinical outcomes and survival predictors of recurrent RLS with multiple tumors remain to be explored.

Methods

Patients with recurrent RLS were retrospectively analyzed. Univariate and multivariate analysis was performed to find independent prognostic factors that were correlated with Overall survival (OS) or progression-free survival (PFS). Factors significant in univariate analysis were further included into multivariate Cox proportional hazards regression model. The nomogram model was built to predict the survival status of patients. Variables that were significant in multivariable analysis were added to the internally validated nomogram models. The analysis of OS and PFS was performed by Kaplan-Meier analysis and log-rank test.

Results

A total of 113 recurrent RLS patients with multiple tumors were enrolled in the study. The 1-, 3-, and 5-years OS (PFS) rates were 70.7% (76.1%), 35.9% (76.1%), and 30.9% (76.1%), respectively. Univariate and multivariate analyses showed that number of surgeries, resection methods, tumor size, status of pathological differentiation, pathological subtypes, and recurrence patterns were important prognostic factors for OS or PFS (each p < 0.05). Nomogram models were established to efficiently predict the prognostic status of patients. Patients with the local recurrence (LR) pattern had a poor prognosis and would derive no survival benefit from combined organ resection and R0/R1 resection (each p < 0.05).

Conclusion

RLS patients recurrence with multiple tumors had a poor prognosis. Those patients should be followed up more frequently after surgery. The strategies of aggressive resection may not improve the survival of patients with LR pattern in the retroperitoneum. Prognostic factors in the efficient nomogram models should be considered in the individualized clinical management of recurrent RLS with multiple tumors.

Correlation Analysis Between Demographic, Surgical, and Pathological Characteristics with Local Recurrence-Free Survival for Surgical Resected Retroperitoneal Liposarcoma

BACKGROUND

As the leading cause of mortality for retroperitoneal liposarcoma (RPLS) cases, postoperative recurrence has complicated and unclear risk factors. This study was conducted to explore the correlations between demographic, surgical, and pathological characteristics with local recurrence-free survival (LRFS) for surgical resected RPLS.

METHODS

RPLS cases that underwent radical operation were considered to be included in this analysis. LRFS rates were estimated based on the Kaplan-Meier method and were compared between groups by the log-rank test. Cox proportional hazard regression models were constructed to identified the predictors of LRFS. Subsequently, the independent predictors acquired from multivariate analyses were used to construct a nomogram.

RESULTS

348 RPLS cases who underwent radical operation were included. Of the 348 cases, 333 had tumor recurrence or with a follow-up period ≥5 years. Thus, 296 (88.9%) of the 333 cases had recurrent disease, and the median LRFS duration of 296 recurrence cases was 17.0 (95% confidence interval (CI) 13.2-20.8) months. Multivariate analysis identified the preoperative neutrophil/lymphocyte ratio (NLR), surgical frequency, operative time, tumor shape, histological subtype, and tumor necrosis as independent predictors of LRFS. Based on above independent predictors, a nomogram was constructed to predict the 1-, 3-, and 5-year LRFS of surgical resected RPLS.

CONCLUSION

Elevated preoperative NLR, ≥2nd time surgical frequency, extended operation time, irregular tumor shape, no well-differentiated histological subtype, and tumor necrosis could be used as predictors of LRFS for surgical resected RPLS.

Insight of a lipid metabolism prognostic model to identify immune landscape and potential target for retroperitoneal liposarcoma

Introduction

The exploration of lipid metabolism dysregulation may provide novel perspectives for retroperitoneal liposarcoma (RPLS). In our study, we aimed to investigate potential targets and facilitate further understanding of immune landscape in RPLS, through lipid metabolism-associated genes (LMAGs) based prognostic model.

Methods

Gene expression profiles and corresponding clinical information of 234 cases were enrolled from two public databases and the largest retroperitoneal tumor research center of East China, including cohort-TCGA (n=58), cohort-GSE30929 (n=92), cohort-FD (n=50), cohort-scRNA-seq (n=4) and cohort-validation (n=30). Consensus clustering analysis was performed to identify lipid metabolism-associated molecular subtypes (LMSs). A prognostic risk model containing 13 LMAGs was established using LASSO algorithm and multivariate Cox analysis in cohort-TCGA. ESTIMATE, CIBERSORT, XCELL and MCP analyses were performed to visualize the immune landscape. WGCNA was used to identify three hub genes among the 13 model LMAGs, and preliminarily validated in both cohort-GSE30929 and cohort-FD. Moreover, TIMER was used to visualize the correlation between antigen-presenting cells and potential targets. Finally, single-cell RNA-sequencing (scRNA-seq) analysis of four RPLS and multiplexed immunohistochemistry (mIHC) were performed in cohort-validation to validate the discoveries of bioinformatics analysis.

Results

LMS1 and LMS2 were characterized as immune-infiltrated and -excluded tumors, with significant differences in molecular features and clinical prognosis, respectively. Elongation of very long chain fatty acids protein 2 (ELOVL2), the enzyme that catalyzed the elongation of long chain fatty acids, involved in the maintenance of lipid metabolism and cellular homeostasis in normal cells, was identified and negatively correlated with antigen-presenting cells and identified as a potential target in RPLS. Furthermore, ELOVL2 was enriched in LMS2 with significantly lower immunoscore and unfavorable prognosis. Finally, a high-resolution dissection through scRNA-seq was performed in four RPLS, revealing the entire tumor ecosystem and validated previous findings.

Discussion

The LMS subgroups and risk model based on LMAGs proposed in our study were both promising prognostic classifications for RPLS. ELOVL2 is a potential target linking lipid metabolism to immune regulations against RPLS, specifically for patients with LMS2 tumors.

Malignant adipocytic tumours: A 20‑year single‑centre retrospective study

Adipocytic tumours are the most common soft tissue neoplasms. Among them, liposarcoma is the most frequent malignant neoplasm. However, to the best of our knowledge, no previously published study has assessed the evolution and oncological prognosis of the different subtypes of liposarcoma at the retroperitoneal level compared with at other locations. The present study is a retrospective observational study in which all patients were operated on between October 2000 and January 2020 with a histological diagnosis of liposarcoma. Variables, such as age, sex, location, histological type, recurrence, type of treatment and mortality, among others, were analysed. The patients were divided into two groups: Group A (retroperitoneal location) and group B (non-retroperitoneal location). A total of 52 patients with a diagnosis of liposarcoma (17 women and 35 men) and a mean age of 57.2±15.9 years were assessed. A total of 16 patients were classified into group A and 36 into group B. The OR of recurrence was 1.5 (P=0.02) for R1 vs. R0 resection in group A. The OR of recurrence in group B for R1 vs. R0 resection was 1.8 (P=0.77), whereas for R2 vs. R0 resection, the OR was 69 (P=0.011). In conclusion, 52 cases of malignant adipocytic tumours collected during 2000-2020 were analysed with the new World Health Organization classification (updated 2020). Although its recurrence potential and capacity for distant metastasis depended on each histological type, surgical treatment with unaffected margins was the main prognostic factor for survival. The present study identified differences in relation to the survival of each histological subtype and its location, finding greater survival in dedifferentiated liposarcoma, myxoid liposarcoma and pleomorphic liposarcoma located at the extraperitoneal level than in the retroperitoneal location. Resectability was not influenced by liposarcoma location.

Predictive factors and a novel nomogram for recurrence of primary retroperitoneal liposarcoma: Comprehensive analysis of 128 cases

Since primary retroperitoneal liposarcoma (PRPLS) is rare in the clinic, related clinical studies are lacking. The present study was designed to investigate the predictive factors of short-term (≤1 year) recurrence (STR) and construct a novel nomogram of local recurrence-free survival (LRFS) for surgically resected PRPLS. A total of 128 PRPLS cases who underwent radical surgery were retrospectively analyzed. Based on the interval from the operation to tumor recurrence, the predictors of STR were screened using univariate and multivariate logistic regression analyses. Cox proportional hazard regression models were applied to identify the predictors of LRFS. Furthermore, the independent predictors acquired from multivariate analyses were used to construct a nomogram. Multivariate logistic regression analysis revealed that age ≥55 years [odds ratio (OR)=5.607, P=0.010], operative time ≥260 min (OR=9.716, P=0.005) and tumor necrosis (OR=3.781, P=0.037) were independent risk factors of STR for PRPLS. In the Cox regression analysis, clinical symptoms [hazard ratio (HR)=1.746, P=0.017], resection method (OR=0.370, P=0.021) and de-differentiated histological subtype (HR=1.975, P=0.048) were identified as independent predictors of LRFS. Subsequently, the independent predictors acquired from multivariate analyses were used to construct a nomogram for LRFS. Age, operative time, tumor necrosis, clinical symptoms, resection method and histological subtype were related to recurrence for surgically resected PRPLS and a novel nomogram was constructed based on the above predictors.

Human intravital microscopy in the study of sarcomas: an early trial of feasibility

Sarcomas comprise a vast and heterogenous group of rare tumors. Because of their diversity, it is challenging to study sarcomas as a whole with regard to their biological and molecular characteristics. This diverse set of tumors may also possess differences related to their tumor-associated vasculature, which in turn may impact the ability to deliver systemic therapies (e.g., chemotherapy, targeted therapies, and immunotherapy). Consequently, response to systemic treatment may also be variable as these depend on the ability of the therapy to reach the tumor target via the tumor-associated vasculature. There is a paucity of data regarding sarcoma-related tumor vessels, likely in part to the rarity and heterogeneity of this cancer as well as the previously limited ability to image tumor-associated vessels in real time. Our group has previously utilized confocal fluorescent imaging technology to observe and characterize tumor-associated vessels in real time during surgical resection of tumors, including cutaneous melanoma and carcinomatosis implants derived from gastrointestinal, gynecological, or primary peritoneal (e.g., mesothelioma) tumors. Our prior studies have demonstrated the feasibility of real-time, human intravital microscopy in the study of these tumor types, leading to early but important new data regarding tumor vessel characteristics and their potential implications on drug delivery and efficacy. In this brief report, we present our latest descriptive findings in a cohort of patients with sarcoma who underwent surgical resection and real-time, intravital microscopy of their tumors. Overall, intravital imaging was feasible during the surgical resection of large sarcomas.

Clinical trial registrations

ClinicalTrials.gov, identifier NCT03517852; ClinicalTrials.gov, identifier NCT03823144.

Survival of a patient with multiple-recurrent giant retroperitoneal dedifferentiated liposarcoma for 15 years: A case report

Background

Retroperitoneal liposarcoma (RPLS) is a variety of soft tissue sarcoma that originates from mesenchymal cells. A tumor measuring greater than 30 cm is called a “giant liposarcoma.” A part of the neoplasm tends to grow in size, recur locally, or metastasize distantly. In those with such a condition, long-term survival is uncommon. Therefore, it is necessary to present a uniform and optimized program to improve the prognosis.

Methods

By successfully treating a multiple-recurrent giant retroperitoneal dedifferentiated liposarcoma (RP DDLPS) in July 2010, we hope to devise more comprehensive strategies to improve diagnosis, therapy, and outcome.

Results

In July 2010, we thoroughly resected a giant multifocal RPLS with a concomitant part of the gastric wall. The histopathological examination revealed a high-grade (grade III) dedifferentiated liposarcoma. The patient was discharged uneventfully on the 15th postoperative day. She relapsed after 16 months and needed another complete excision. After 9 months, she died after the fourth recidive. The patient had experienced four recurrences and underwent operations with 15 years of follow-up.

Conclusions

The above demonstrates that we were able to successfully treat the multirecurrent giant RPLS, despite the patient’s poor medical condition, with meticulous management. Moreover, this indicates that long-term survival could be achieved for high-grade RP DDLPS.

Analysis of potential risk factors in the survival of patients with primary retroperitoneal liposarcoma

INTRODUCTION

The present work is an observational study of a series of variables regarding overall survival and disease-free survival in patients diagnosed with primary liposarcoma.

METHODS

The study is prospective with retrolective data collection that includes all patients with primary liposarcoma referred to Hospital Son Espases University Hospital, Palma de Mallorca, Spain from January 1990 to December 2019.

RESULTS

The study includes 50 patients and the compartment surgery was performed in 18 patients (36%) of cases. The mean overall survival of the sample was 15.57 years (95% CI: 12.02-19.12) and the mean disease-free survival was 6.70 years (95% CI: 4.50-8.86).

CONCLUSION

Compartment surgery has not shown benefits in terms of overall survival and disease-free survival. The ASA classification (≥3) predicts a poor prognosis in both overall survival and disease-free survival. Resection with free margins, described on the pathological results and defined in this work as R0, show better disease-free survival.

Multidimensional characteristics, prognostic role, and preoperative prediction of peritoneal sarcomatosis in retroperitoneal sarcoma

Background

Peritoneal sarcomatosis (PS) could occur in patients with retroperitoneal sarcomas (RPS). This study aimed to expand the understanding of PS on its characteristics and prognostic role, and develop a nomogram to predict its occurrence preoperatively.

Methods

Data of 211 consecutive patients with RPS who underwent surgical treatment between 2011 and 2019 was retrospectively reviewed. First, the clinicopathological characteristics of PS were summarized and analyzed. Second, the disease-specific survival (DSS) and recurrence-free survival (RFS) of patients were analyzed to evaluate the prognostic role of PS. Third, preoperative imaging, nearly the only way to detect PS preoperatively, was combined with other screened risk factors to develop a nomogram. The performance of the nomogram was assessed.

Results

Among the 211 patients, 49 (23.2%) patients had PS with an incidence of 13.0% in the primary patients and 35.4% in the recurrent patients. The highest incidence of PS occurred in dedifferentiated liposarcoma (25.3%) and undifferentiated pleomorphic sarcoma (25.0%). The diagnostic sensitivity of the preoperative imaging was 71.4% and its specificity was 92.6%. The maximum standardized uptake value (SUVmax) was elevated in patients with PS (P&lt;0.001). IHC staining for liposarcoma revealed that the expression of VEGFR-2 was significantly higher in the PS group than that in the non-PS group (P = 0.008). Survival analysis (n =196) showed significantly worse DSS in the PS group than in non-PS group (median: 16.0 months vs. not reached, P &lt; 0.001). In addition, PS was proven as one of the most significant prognostic predictors of both DSS and RFS by random survival forest algorithm. A nomogram to predict PS status was developed based on preoperative imaging combined with four risk factors including the presentation status (primary vs. recurrent), ascites, SUVmax, and tumor size. The nomogram significantly improved the diagnostic sensitivity compared to preoperative imaging alone (44/49, 89.8% vs. 35/49, 71.4%). The C-statistics of the nomogram was 0.932, and similar C-statistics (0.886) was achieved at internal cross-validation.

Conclusion

PS is a significant prognostic indicator for RPS, and it occurs more often in recurrent RPS and in RPS with higher malignant tendency. The proposed nomogram is effective to predict PS preoperatively.

Patients with first recurrent retroperitoneal sarcoma that can be macroscopically completely resected can achieve comparable outcomes with that of primary patients after en bloc resection of tumor and adjacent organs

The outcomes of patients with primary retroperitoneal sarcoma (RPS) are significantly superior to those with recurrence. En bloc resection of tumor and adjacent organs is recommended in primary RPS. However, whether en bloc resection of tumor and adjacent organs can benefit recurrent patients or some recurrent patients is unclear. We compared the outcomes of patients with primary RPS, first recurrence (RPS-Rec1), and ≥2 recurrences (≥RPS-Rec2) to evaluate the value and criteria for en bloc resection of tumor and adjacent organs in recurrent cases. We evaluated the safety of en bloc resection of tumor and adjacent organs by assessing operation time, blood loss volume, postoperative morbidities (POM), and efficacy by comparing local recurrence and peritoneal metastasis (LR-PM), distant metastasis, progression-free survival (PFS), and overall survival (OS). A total of 101, 47, and 30 patients with primary RPS, RPS-Rec1, and ≥RPS-Rec2 were included, respectively. Recurrent RPS invaded more adjacent organs and surrounding fat tissue than primary RPS. The operation time, amount of blood loss, incidence of grade III–V POM, LR-PM rate, PFS, and OS in the RPS-Rec1 group were similar to those of the primary group, both of which were significantly superior to those of the ≥RPS-Rec2 group. Macroscopically incomplete resection and high-grade RPS rather than first recurrence were independent risk factors for LR-PM, PFS, and OS. In conclusion, the safety and efficacy of en bloc resection of tumor and adjacent organs in RPS-Rec1 were comparable with those in primary RPS but significantly superior to those of ≥RPS-Rec2. For RPS-Rec1, comparable outcomes to patients with primary RPS can be achieved, particularly in those in whom a macroscopically complete resection is achieved.

Myxomatous Liposarcoma of the Mediastinum: A Review of the Literature

Myxomatous liposarcoma is an extremely rare type of mediastinal tumour that manifests in a manner comparable to other lung pathologies. Chest pain, shortness of breath, and dysphagia are the common presenting complaints. Radiological examinations or postoperative histological examinations provide the majority of the diagnostic evidence. The cornerstone of therapy consists of surgery and sometimes chemotherapy. Those who are afflicted have a better chance of experiencing favourable outcomes if they receive a diagnosis and treatment quickly.

Tsp2 Facilitates Tumor-associated Fibroblasts Formation and Promotes Tumor Progression in Retroperitoneal Liposarcoma

Retroperitoneal liposarcoma (RLPS) is the most common subtype of retroperitoneal soft tissue sarcoma, characterized by a high recurrence rate and insensitivity to radiotherapy and chemotherapy. The function of tumor microenvironmental components, especially tumor-associated fibroblasts (TAFs), remains unclear in RLPS. The crosstalk between tumor cells and stromal cells should be clarified for therapy target discovery in RLPS. In this study, we demonstrated that TAFs from dedifferentiated liposarcoma (DDLPS) could attract LPS cells and promote their proliferation and migration. However, although α-SMA is positively expressed in RLPS, its expression does not indicate prognosis. By screening differentially expressed genes, performing Oncomine visualization, TCGA gene expression correlation analysis and qPCR verification, we determined that thrombospondin-2 (THBS2) gene expression was related to TAFs. The expression of Tsp2 protein, which was encoded by THBS2, was correlated with α-SMA expression, and it was an independent predictive factor for disease-free survival and recurrence-free survival in patients with RLPS. In vitro, Tsp2 facilitated the transformation of bone marrow-derived fibroblasts (BMFs) to TAFs and promoted the malignant biological behaviors of LPS cells by activating the MAPK/MEK/ERK pathway. Therefore, suppression of Tsp2 is expected to be a promising treatment method for RLPS patients.

Retroperitoneal Sarcomas: Histology Is Everything

Retroperitoneal sarcomas (RPS) are a rare subset of soft tissue sarcoma that are composed of only a few histologic subtypes, each with a distinct tumor biology, clinical presentation, preferred treatment strategy, recurrence risk, and surveillance plan. In the modern era of precision medicine, our understanding of the implications of subtype tumor biology and anatomic location has led to a more nuanced, histology-specific approach to therapy, including surgery, neoadjuvant radiation therapy, and/or chemotherapy. This article provides a summary of recent updates to the management of RPS.

Management of Locally Recurrent Retroperitoneal Sarcoma in the Adult: An Updated Consensus Approach from the Transatlantic Australasian Retroperitoneal Sarcoma Working Group

BACKGROUND

Surgery is the mainstay of treatment for retroperitoneal sarcoma (RPS), but local recurrence is common. Biologic behavior and recurrence patterns differ significantly among histologic types of RPS, with implications for management. The Transatlantic Australasian RPS Working Group (TARPSWG) published a consensus approach to primary RPS, and to complement this, one for recurrent RPS in 2016. Since then, additional studies have been published, and collaborative discussion is ongoing to address the clinical challenges of local recurrence in RPS.

METHODS

An extensive literature search was performed, and the previous consensus statements for recurrent RPS were updated after review by TARPSWG members. The search included the most common RPS histologic types: liposarcoma, leiomyosarcoma, solitary fibrous tumor, undifferentiated pleomorphic sarcoma, and malignant peripheral nerve sheath tumor.

RESULTS

Recurrent RPS management was evaluated from diagnosis to follow-up evaluation. For appropriately selected patients, resection is safe. Nomograms currently are available to help predict outcome after resection. These and other new findings have been combined with expert recommendations to provide 36 statements, each of which is attributed a level of evidence and grade of recommendation. In this updated document, more emphasis is placed on histologic type and clarification of the intent for surgical treatment, either curative or palliative. Overall, the fundamental tenet of optimal care for patients with recurrent RPS remains individualized treatment after multidisciplinary discussion by an experienced team with expertise in RPS.

CONCLUSIONS

Updated consensus recommendations are provided to help guide decision-making for treatment of locally recurrent RPS and better selection of patients who would potentially benefit from surgery.

Case Report: Retroperitoneal Sarcoma in Six Operations: Our Experience in Operative Management of Blood Vessels

Here we introduce a case of retroperitoneal liposarcoma, which is characterized by repeated recurrences after surgery, and has undergone a total of 6 operations. The diameter of the tumor was about 26 cm at the time of the patient's diagnosis. The imaging examination revealed that the surrounding organs and blood vessels were invaded, which brought great challenges to radical resection. The postoperative pathology of the patient’s first operation was dedifferentiated liposarcoma, and some areas showed myxofibrosarcoma differentiation. With the recurrence of sarcoma, myxofibrosarcoma dedifferentiated into rhabdomyosarcoma, and malignant fibrous histiocytoma appeared in some areas. How to treat this type of patient after recurrence? How to deal with blood vessels wrapped by sarcoma during surgery? The medical community has not yet reached the same conclusion. We describe the process of treating the patient and the experience of dealing with blood vessels during surgery.

Management of retroperitoneal sarcoma involving the iliac artery: Single-center surgical experience

BACKGROUND

Management of retroperitoneal sarcoma (RPS) involving the iliac artery is challenging and requires the concerted efforts of multidisciplinary team (MDT) members during surgical treatment.

AIM

To summarize the clinicopathologic features of RPS involving the iliac artery and our retroperitoneal soft tissue tumor MDT surgical experience.

METHODS

In this retrospective study, 15 patients with RPS involving the iliac artery who underwent surgery at our retroperitoneal soft tissue tumor center from July 2004 to June 2020 were analyzed. Statistical analyses were performed by Student’s t-test with SPSS 16.0.

RESULTS

Complete tumor resection (R0/R1) and iliac artery reconstruction were achieved in all 15 patients. All the operations were successful, with no serious complications or perioperative death. Resection with bilateral iliac artery reconstruction required a higher intraoperative blood transfusion volume than resection with unilateral iliac artery reconstruction. Recurrent cases were more likely to bleed and required a higher blood transfusion volume than primary cases. As of January 2021, 11 patients were alive, and 4 had died. Local recurrence occurred in two patients, one of whom developed liver metastasis.

CONCLUSION

Resection of RPS involving iliac vessels is feasible and effective when performed by MDT members. Iliac artery oncovascular resection and reconstruction are key to a successful operation. Adequate blood preparation is important for successful completion of surgery.

Hyper-accuracy three-dimensional reconstruction as a tool for better planning of retroperitoneal liposarcoma resection: A case report

BACKGROUND

Well-differentiated liposarcoma is the second most common pathologic type of retroperitoneal sarcoma. It is characterized by a huge mass, but multiple organ invasions are common. Surgery is the only treatment option for potential cure. Hyper-accuracy three-dimensional (3D) reconstruction is widely used in robotic partly nephrectomy owing to its ability to visualize overlapping anatomy.

CASE SUMMARY

A 54-year-old man was admitted for progressive abdominal distension over the preceding 2 mo. Computed tomography revealed a 32 cm × 21 cm × 12 cm lipomatous mass. Hyper-accuracy 3D reconstruction was performed because of the complex relationship between the mass and nearby tissue. The patient underwent surgical resection, and the tumor did not recur for over 16 mo.

CONCLUSION

Hyper-accuracy 3D reconstruction is useful for operative planning owing to its intuitiveness and precise determination of anatomical structures in both tumors and nearby tissues.

Analysis of potential risk factors in the survival of patients with primary retroperitoneal liposarcoma

INTRODUCTION

The present work is an observational study of a series of variables regarding overall survival and disease-free survival in patients diagnosed with primary liposarcoma.

METHODS

The study is prospective with retrolective data collection that includes all patients with primary liposarcoma referred to Hospital Son Espases University Hospital, Palma de Mallorca, Spain from January 1990 to December 2019.

RESULTS

The study includes 50 patients and the compartment surgery was performed in 18 patients (36%) of cases. The mean overall survival of the sample was 15.57 years (95% CI: 12.02-19.12) and the mean disease-free survival was 6.70 years (95% CI: 4.50-8.86).

CONCLUSION

Compartment surgery has not shown benefits in terms of overall survival and disease-free survival. The ASA classification (≥3) predicts a poor prognosis in both overall survival and disease-free survival. Resection with free margins, described on the pathological results and defined in this work as R0, show better disease-free survival.

Analysis of Differentiation Changes and Outcomes at Time of First Recurrence of Retroperitoneal Liposarcoma by Transatlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG)

BACKGROUND

Local recurrence following resection of retroperitoneal liposarcoma (RLPS) is common. Well-differentiated (WD) and dedifferentiated (DD) RLPS are distinct entities with differing outcomes. A few reports suggest that WDLPS can recur as DDLPS and that DDLPS can recur as WDLPS. This study evaluates whether this change in differentiation from the primary tumor to the first local recurrence impacts long-term outcomes.

METHODS

Retrospective review from 22 sarcoma centers identified consecutive patients who underwent resection for a first locally recurrent RLPS from January 2002 to December 2011. Outcomes measured included overall survival, local recurrence, and distant metastasis.

RESULTS

A total of 421 RPLS patients were identified. Of the 230 patients with primary DDLPS, 34 (15%) presented WDLPS upon recurrence (DD → WD); and of the 191 patients with primary WDLPS, 54 (28%) presented DDLPS upon recurrence (WD → DD). The 6-year overall survival probabilities (95% CI) for DD → DD, DD → WD, WD → WD, and WD → DD were 40% (32-48%), 73% (58-92%), 76% (68-85%), and 56% (43-73%) (p < 0.001), respectively. The 6-year second local recurrence incidence was 66% (59-73%), 63% (48-82%), 66% (57-76%), and 77% (66-90%), respectively. The 6-year distant metastasis incidence was 13% (9-19%), 3% (0.4-22%), 5% (2-11%), and 4% (1-16%), respectively. On multivariable analysis, DD → WD was associated with improved overall survival when compared with DD → DD (p < 0.001). Moreover, WD → DD was associated with a higher risk of LR (p = 0.025) CONCLUSION: A change in RLPS differentiation from primary tumor to first local recurrence appears to impact survival. These findings may be useful in counseling patients on their prognosis and subsequent management.

Survival analysis and treatment strategies for limb liposarcoma patients with metastasis at presentation

Limited data exist on patients with limb liposarcoma (LLS) with metastasis at presentation Moreover, the potential prognostic factors of this patient population are poorly documented because of its rarity. Therefore, we conducted this study to evaluate the clinicopathologic characteristics and prognostic factors for patients with metastatic LLS.All patients with LLS with metastasis at presentation from 1975 to 2016 were identified by using the Surveillance, Epidemiology, and End Results (SEER) database. The following clinical data were derived from this clinical database: age, sex, histologic grade, subtype, size of tumor, surgery, radiotherapy, chemotherapy, vital status, cause of death, and survival duration. The Kaplan-Meier method was performed to calculate median survival time and draw survivorship curves. Cox-proportional hazards regression model was used to reveal the statistical independence between various variables.The present study collected 184 cases from SEER database for survival analysis. Mean age was 57.8 years with 63.6% (n = 117) men. The 3-year overall survival (OS) and cancer-specific survival (CSS) rates of this population were 27.8% and 30.1%, respectively. Univariate analysis revealed that age, tumor grade, and surgery were significantly correlated with survival. Sex and tumor size did not reach significant predictor status of survival. Multivariate analysis revealed that age at diagnosis <60, low tumor grade, and local surgery were significantly correlated with improved OS and CSS.Patients with LLS with metastasis at diagnosis experienced quite poor prognosis. Currently, surgery for the primary tumor significantly prolonged the survival of those patients, whereas chemotherapy and radiotherapy need to be further confirmed.

Myogenic dedifferentiation is associated with poor outcomes in retroperitoneal dedifferentiated liposarcomas

Sarcomas are a heterogenous group of malignant tumors with origin or mesenchymal differentiation, they comprise 1–2% of all solid tumors. Retroperitoneum is the second most frequent site affected. Prognosis is worse compared to the limbs, with a 5y OS of 36–58%, and 50–60% patients will relapse. Dedifferentiated liposarcomas (ddLPS) are more aggressive, it is known that presence of a de-differentiated component increases the probability of distant recurrence and lowers OS. There is little information about the specific impact of each type of de-differentiation. To determine if the presence of myogenic differentiation markers in DDLPS is an adverse prognostic factor. A retrospective, observational, analytic cohort study was performed. Cases identified from the electronic clinical files from the National Cancer Institute in Mexico City, we included cases from January 1st 2005 to December 31st 2016. We correlated the presence of expression of myogenic markers (Smooth muscle actin, Calponin, H-caldesmon, Desmin and Myogenin) in the dedifferentiated component of DDLPS with overall survival and surgical outcomes. One hundred and forty-three cases were analyzed. Eighty-two were liposarcomas, and 38 had a dedifferentiated component. Of these 38 cases, 21(55.3%) were males and, 17(44.7%) were females. Median age was 54.1(27–79) years, median tumor size was 28 cm (13–56). Most patients had locally advanced disease: 32(84.2%) were in stage IIIB. 2.6% had metastatic disease and 5(13.2%) had stage Ib at diagnosis. Myogenic marker expression was found in 18.4% of cases; these patients had a worse median survival than cases with no myogenic expression: 18 months (95% CI 15.4–20.5) vs 32 months (95% CI 21.8–42.1) p = 0.01, we also found a relation with higher postoperative morbidity in these cases (p = 0.045). The presence of myogenic differentiation markers might be associated with a worse prognosis, in our series it corelated with worse OS, however it is not a common event. Relation with surgical morbidity is to be analyzed in further studies.

The role of 18 F-FDG PET/CT in retroperitoneal sarcomas-A multicenter retrospective study

BACKGROUND

The role of ¹⁸ F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸ F-FDG PET/CT) in the evaluation of retroperitoneal sarcomas is poorly defined. We evaluated the correlation of maximum standardized uptake value (SUVmax) with pathologic tumor grade in the surgical specimen of primary retroperitoneal dedifferentiated liposarcoma (DDLPS) and leiomyosarcoma (LMS).

METHODS

Patients with the above histological subtypes in three participating institutions with preoperative ¹⁸ F-FDG PET/CT scan and histopathological specimen available for review were included. The association between SUVmax and pathological grade was assessed. Correlation between SUVmax and relapse-free survival (RFS) and overall survival (OS) were also studied.

RESULTS

Of the total 58 patients, final pathological subtype was DDLPS in 44 (75.9%) patients and LMS in 14 (24.1%) patients. The mean SUVmax was 8.7 with a median 7.1 (range, 2.2-33.9). The tumors were graded I, II, III in 6 (10.3%), 35 (60.3%), and 17 (29.3%) patients, respectively. There was an association of higher histological grade with higher SUVmax (r_s  = 0.40, p = .002). Increasing SUVmax was associated with worse RFS (p = .003) and OS (p = .003).

CONCLUSION

There is a correlation between SUVmax and pathologic tumor grade; increasing SUVmax was associated with worse OS and RFS, providing a preoperative noninvasive surrogate marker of tumor grade and biological behavior.

Characteristics of primary and repeated recurrent retroperitoneal liposarcoma: outcomes after aggressive surgeries at a single institution

OBJECTIVE

This study sought to investigate the characteristics of primary and repeated recurrent retroperitoneal liposarcoma.

METHODS

Patients treated with primary or recurrent retroperitoneal liposarcoma between 2005 and 2018 were retrospectively reviewed. Survival time analysis of recurrence-free survival and overall survival was conducted using Kaplan-Meier analysis and log-rank test.

RESULTS

Fifty-two patients with primary retroperitoneal liposarcoma were analysed. Amongst them, 46 patients (88%) had undergone surgery. Histologic grades included well-differentiated (n = 21), dedifferentiated (n = 21), myxoid (n = 3) and pleomorphic (n = 1) subtypes. The patients undergoing R0 resection in the first surgery had significantly higher recurrence-free survival rates compared with the patients undergoing non-R0 resection (3-year recurrence-free survival: 80 versus 38%; 5-year recurrence-free survival: 49 versus 29%, P = 0.033). Although overall survival rates tended to be higher in the patients undergoing R0 resection compared with the non-R0 resection, it did not reach to a statistical significant difference (5-year overall survival: 93 versus 75%; 10-year overall survival: 93 versus 59%, P = 0.124). The recurrence rates were 65, 67, 73 and 100%, and the median recurrence-free survival times were 46, 20, 9 and 3 months after the first, second, third and fourth surgeries, respectively. The 5-year overall survival rates were 82, 69, 40 and 0% after the first, second, third and fourth surgeries, respectively.

CONCLUSIONS

With repeated recurrence and surgeries, the time to recurrence decreased and the recurrence rate increased. R0 resection in the first surgery was considered the most important for longer recurrence-free survival and radical cure.

Retroperitoneal sarcomas: Outcomes of repeated resections

Purpose

Retroperitoneal sarcomas (RPS) are rare malignant tumors arising from mesenchymal cells. The objective of this study was to review the treatment experiences and to identify prognostic factors for overall survival (OS) after primary resection and subsequent reoperations for recurrences.

Methods

The medical records of patients who underwent resection for RPS at our institution between June 2002 and December 2016 were retrospectively reviewed. Univariate and multivariable Cox proportional hazards modeling was used to assess the prognostic factors for OS.

Results

A total of 48 patients were enrolled. On multivariable analysis in primary resection group, the FNCLCC (Fédération Nationale des Centres de Lutte Contre le Cancer) grade was a significant prognostic factor for OS (P=0.006). The patients who received chemotherapy after primary resection were significantly associated with poor prognosis (P=0.009). The 5-year OS rate after primary resection (n=48) were 58.1% and the 5-year cumulative reoperation rate after primary resection was 62.5%. After second resection for recurrence after primary resection (n=23), the 5-year OS rate was 64.3%. There was a tendency towards decreased surgery-free survival rate as the number of repeated resections for recurrent RPS increased. In the subset of patients (n=16) who underwent more than 3 repeated resections at our institute, the 5-year OS rate was 75.0%, indicating that repeated resections are not associated with worse outcome.

Conclusion

Only low tumor grade was an independent favorable prognostic factor for OS. Although the prognosis for RPS remains poor, repeated resections for recurrence are not associated with poor prognosis. Aggressive surgical strategies for recurred RPS patients are warranted.

Clinical features of multiply recurrent retroperitoneal liposarcoma: A single-center experience

BACKGROUND

To elucidate the clinicopathological features of multiply recurrent retroperitoneal liposarcoma referred to a tertiary center.

METHODS

We retrospectively analyzed the clinical data of 40 patients with pathologically proven primary retroperitoneal liposarcoma treated between January 2015 and June 2019.

RESULTS

The initial pathology was well-differentiated liposarcoma (WDLS) in 23 patients, dedifferentiated liposarcoma (DDLS) in 15 patients, and myxoid liposarcoma in two patients. Before and after referral to our hospital, the patients underwent 142 surgeries (median number of surgeries: 3) for initial and recurrent tumors. Of these, 35 (87.5%) patients underwent surgeries for recurrent tumors. In 11 (47.8%) of the 23 patients with initial WDLS, pathological progression (PP) to DDLS was observed in recurrent tumors at the median interval of 7.8 years. In eight patients (72.7%), the PP occurred at the first recurrence. In contrast, all 15 patients with DDLS recurred as DDLS. Distant metastases developed in eight patients (34.8%) with WDLS and five patients (29.4%) with DDLS/myxoid subtype. All eight WDLS patients who developed metastasis were alive with disease at the median interval of 3.6 years, whereas four of the five patients with primary diagnosis of DDLS/myxoid subtype died at the median interval of 5.6 months from the development of metastasis. The 5-year overall survival of the patients with initial WDLS and those with DDLS/myxoid subtype were 100% and 67.4% (p = 0.0006), respectively.

CONCLUSIONS

The prognosis of the initial-WDLS patients was favorable despite multiple recurrences. In WDLS patients, if distant metastases develop, it is possible to remain alive with disease for years.

A novel nomogram for predicting local recurrence-free survival after surgical resection for retroperitoneal liposarcoma from a Chinese tertiary cancer center

BACKGROUND

Local recurrence is the most difficult postoperative challenge and the leading cause of death in patients with retroperitoneal liposarcoma (RLPS). We aimed to establish a postoperative nomogram exclusively focused on RLPS for predicting local recurrence-free survival (LRFS).

METHODS

A cohort of 124 patients after surgical resection with curative intent in the Peking University Cancer Hospital Sarcoma Center were included in the study. Demographic, clinicopathologic, and treatment variables were analyzed using the Cox regression model. Significant clinically relevant variables in multivariable analysis were incorporated into the RLPS-specific nomogram. The discriminative ability and predictive accuracy of the nomogram were assessed by calculating the concordance index and drawing a calibration plot.

RESULTS

At a median follow-up of 26.5 (interquartile range 10.9-39.4) months, 71 patients had recurrent disease. The 3-year and 5-year LRFS rates were 35.6% (95% confidence interval, 27.0-46.9%) and 28.2% (95% CI 15.8-38.6%), respectively. Multivariate analysis identified the French Federation of Cancer Centers Sarcoma Group (FNCLCC) grade and completeness of resection as independent predictors of LRFS. Variables included in our nomogram were: presentation status, multifocality, completeness of resection, histologic subtypes, and FNCLCC grade. The concordance index of our nomogram was 0.732 (95% CI 0.667-0.797) and the calibration plot was excellent.

CONCLUSIONS

Our novel nomogram for patients with resected RLPS could improve recurrence risk stratification to explore molecular analysis associated with recurrence.

Identification of TYMS as a promoting factor of retroperitoneal liposarcoma progression: Bioinformatics analysis and biological evidence

Retroperitoneal liposarcoma (RLPS) is one of the most common types of retroperitoneal sarcomas, and has a high recurrence rate. There is an urgent need to further explore its pathogenesis and develop more effective treatment strategies. The aim of the present study was to identify potential driver genes of RLPS through bioinformatics analysis and molecular biology to elucidate potential targets that are suitable for further analysis for the treatment of RLPS. Differentially expressed genes (DEGs) between liposarcoma and normal fatty (NF) tissues were identified based on microarray data through bioinformatics analysis, and thymidylate synthase (TYMS) was selected from the DEGs, based on high content screening (HCS). TYMS expression was evaluated in RLPS tumor tissues and cell lines. A total of 21 RLPS tissues and 10 NF frozen tissues were used for reverse transcription-quantitative PCR, and 47 RLPS formalin-fixed specimens were used for immunohistochemical analysis. The effect of TYMS downregulation on cell proliferation, apoptosis, cell cycle progression, and cell migration and invasion were evaluated using lentivirus-mediated short hairpin RNA. The underlying mechanisms of TYMS in RLPS were examined by protein microarray and verified by western blotting. A total of 855 DEGs were identified. TYMS knockdown had the most notable effect on the proliferative capacity of RLPS cells according to the HCS results. TYMS mRNA expression levels were higher in RLPS tissues compared with NF tissues (P<0.001). TYMS expression was higher in high-grade RLPS tissues compared with low-grade RLPS tissues (P=0.003). The patients with positive TYMS expression had a worse overall survival (OS) and disease-free survival (DFS) compared with the patients with negative TYMS expression (OS, P=0.024; DFS, P=0.030). The knockdown of TYMS reduced proliferation, promoted apoptosis, facilitated cell cycle progression from G₁ to S phase, and reduced cell migration and invasion of RLPS cells. Protein microarray analysis and western blotting showed that the Janus Kinase/Signal transducers and activators of transcription pathway was downregulated following TYMS knockdown. In conclusion, TYMS expression is upregulated in RLPS tissues, and downregulation of TYMS reduces RLPS progression.

Role of neoadjuvant Radio-Chemotherapy for retroperitoneal Liposarcoma in primary and secondary surgical intervention

Abstract Background: Approximately 30–40 % of all retroperitoneal soft tissue tumors are sarcomas with liposarcoma prevailing in approximately 50% of these cases. Retroperitoneal liposarcomas typically show a high rate of local recurrence and late distant metastases. The aim of our retrospective analysis was to investigate the efficacy of treatment in our patients with liposarcoma. Methods: Thirty-four consecutive patients underwent surgery in our clinic between October 2004 and November 2017. Liposarcomas arising from the mesenteric or abdominal adipose tissue or the pelvis were excluded. In 2011 we had introduced neo-adjuvant therapy according to IAWS-Guidelines in patients younger than seventy without severe comorbidities to pretreatement. Results: Out of 34 patients, 23 (67,6%) presented with primary and 11 (32,4%) with recurrent disease. In 8 of the 27 patients (30 %), a radical resection (R0) could be achieved, and in 17 patients (63%) resection was marginal (R1). Time to recurrence was not affected by neoadjuvant radiotherapy. Patients that underwent systemic chemotherapy followed by radiotherapy developed earlier recurrences (p = 0.016). Overall survival appeared to be better in the neoadjuvant group but was not significant (0.080) Conclusions: Combining surgical resection with neoadjuvant radiation treatment showed survival benefits in primary but not recurrent disease. Repeated surgery stays a valid approach in carefully selected patients but all patients should be referred to a center of expertise in multimodal treatment approaches for retroperitoneal liposarcomas.

Dedifferentiated retroperitoneal large liposarcoma and laparoscopic treatment: Is it possible and safe? The first literature case report

INTRODUCTION

Soft tissue sarcomas are rare neoplasms often characterized by local invasiveness and distant metastasis with poor prognosis for affected patients. Among the most frequent sarcomas we find well-differentiated and dedifferentiated liposarcomas characterized by a better survival compared to the other histological types. When it is possible the only curative treatment for these neoplasms is surgical resection.

CASE REPORT

We report a case of a 62-year-old caucasian woman with CT abdominal scan that demonstrated a voluminous solid oval mass in the left perirenal space with dislocation of the kidney and in continuity with the anterior renal fascia. After a percutaneous CT-guided biopsy of the mass the histopathological diagnosis was a dedifferentiated retroperitoneal liposarcoma. We performed a laparoscopic surgical resection of the retroperitoneal mass in block with kidney and left adrenal gland.

DISCUSSION

When possible, surgical resection with adequate margins represents the only curative therapeutic option for this pathology. Only a few papers are available in literature which take into consideration the possibility of laparoscopic approach for retroperitoneal masses with better vision of surgical field, reduction of post-operative pain and better cosmesis.

CONCLUSION

A retroperitoneal mass represents a serious diagnostic challenge. The choice of the best surgical procedure can benefit to the patient prognosis. To our opinion laparoscopy can be a safe and successful treatment and it can represent a valid alternative to open surgery. However, we have no randomized controlled trials that compare laparoscopic versus open resection for retroperitoneal liposarcomas.

Giant primary liposarcoma of the anterior mediastinum: A case report

RATIONALE

Liposarcoma is a cancerous mesenchymal tumor and the most common soft-tissue sarcoma that starts in the adipose tissue. Liposarcoma is commonly found in lower extremities and retroperitoneum, but rarely occurs in the mediastinum.

PATIENT CONCERNS

A 63-year-old male was referred to our clinic with a 6-month history of chronic cough and dyspnea.

DIAGNOSE

Chest x-rays demonstrated a large mass occupying the left hemithorax. Contrast-enhanced computed tomography (CT) revealed a large mass in the anterior mediastinum, which caused the extrinsic compression of the main and left pulmonary artery and the right shift of mediastinum. Diagnosis of liposarcoma was confirmed by microscopic examination and immunohistochemistry analysis.

INTERVENTIONS

The patient underwent a thoracotomy for resection of the mediastinal lesion via left thoracic approach.

OUTCOMES

The patient discharged without any complications and has been continuing to follow up in clinic without any complaints.

LESSONS

The primary mediastinal liposarcoma is rare, and we recommend that the liposarcoma should be considered in the differential diagnosis of a patient presenting with a mediastinal mass.